Commit Graph

613 Commits

Author SHA1 Message Date
Hanno Becker
2f41b248c1 Remove calc_verify SSL function pointer 2019-08-29 16:01:32 +01:00
Hanno Becker
8a4b59049b Remove checksum update function pointer from SSL handshake params 2019-08-29 16:01:31 +01:00
Simon Butcher
f0f01e1f0a Merge remote-tracking branch 'origin/pr/630' into baremetal 2019-08-14 16:53:38 +01:00
Simon Butcher
434ab19164 Merge remote-tracking branch 'origin/pr/629' into baremetal 2019-08-14 16:53:13 +01:00
Simon Butcher
0863b2a259 Merge remote-tracking branch 'origin/pr/612' into baremetal 2019-08-14 16:50:13 +01:00
Hanno Becker
b72fc6a648 Don't use const var in initialization of another const var
ARM Compiler doesn't like it.
2019-08-12 18:01:48 +01:00
Hanno Becker
8295ff0b04 tinyCrypt: Don't store public ECDH-share in handshake struct
Instead, write it to the message buffer directly.
2019-08-12 18:01:47 +01:00
Hanno Becker
b1626fb619 tinyCrypt: Remove check for Secp256r1 in SrvKeyExch writing
The use of tinyCrypt is restricted Secp256r1-only, and a check in
ssl_ciphersuite_is_match() ensures that an EC ciphersuite is chosen
only if the client advertised support for Secp256r1, too.
2019-08-12 18:01:47 +01:00
Hanno Becker
9cf087d2e7 Use tinyCrypt only for ECDHE-RSA/ECDSA in SrvKeyExch writing
In a way inconsistent with the rest of the library restricting the
use of tinyCrypt to pure-ECDHE, the previous ServerKeyExchange writing
routine would use tinyCrypt also for ECDHE-PSK-based ciphersuites.
This commit fixes this.
2019-08-12 18:01:47 +01:00
Hanno Becker
7a19633c99 tinyCrypt: Avoid unused var warning by marking vars as unused 2019-08-12 18:01:47 +01:00
Hanno Becker
29d165565c Add MBEDTLS_ECDH_C guards to ECDH code-paths using legacy ECDH
Previously, MBEDTLS_KEY_EXCHANGE_ECDH[E]_XXX_ENABLED would imply
that MBEDTLS_ECDH_C is set, but with the introduction of tinyCrypt
as an alternative ECDH implementation, this is no longer the case.
2019-08-12 18:01:40 +01:00
Hanno Becker
975b9ee3c8 Fix guards around use of legacy ECDH context
mbedtls_ssl_handshake_params::ecdh_ctx should only be guarded
by MBEDTLS_ECDH_C, not by MBEDTLS_ECDSA_C.
2019-08-12 17:05:38 +01:00
Hanno Becker
a3c2c1712c tinyCrypt: Share ECDH secret calculation code-path 2019-08-12 17:05:38 +01:00
Hanno Becker
75f12d1eb9 tinyCrypt: Add ServerKeyExchange parsing code 2019-08-12 17:05:38 +01:00
Hanno Becker
d849c7ca19 tinyCrypt: Hardcode ECDH parameter header
Saves a few bytes of code when tinyCrypt is used.
2019-08-12 17:05:38 +01:00
Hanno Becker
ef982d57bf tinyCrypt: Bind RNG wrapper to tinyCrypt in mbedtls_ssl_setup() 2019-08-12 17:05:38 +01:00
Jarno Lamsa
e12aafbdc7 tinyCrypt: Initial commit towards ECDHE support
This commit is a first step towards using uECC for ECDH
during TLS handshakes.
2019-08-12 17:05:38 +01:00
Hanno Becker
4e46709800 Document precoditions on some HS parsing/writing functions
Eventually, all HS parsing/writing functions should take an arbitrary buffer +
length pair as their argument, and return MBEDTLS_ERR_SSL_BUFFER_TOO_SMALL if
the provided buffer is too short. So far, we've only made a first step by
allowing to pass an arbitrary buffer, but don't yet add bounds checks
throughout. While deliberate for now, this must be clearly documented.
2019-08-12 17:05:03 +01:00
Hanno Becker
7d552fad65 Avoid collision of ssl_xxx_key_exchange_yyy() func names in cli/srv
This makes grepping the functions more difficult, and also leads to compilation failures
when trying to build the library from a single source file (which might be useful for
code-size reasons).
2019-08-12 17:05:03 +01:00
Hanno Becker
7ba0a886bd Fix 'set but not used' ARM compiler warning 2019-08-12 17:05:03 +01:00
Hanno Becker
868cb586cc Rename SSL_PROC_CHK -> MBEDTLS_SSL_CHK 2019-08-12 17:05:03 +01:00
Hanno Becker
9a12243b01 Introduce getter function for RNG context 2019-08-12 17:05:03 +01:00
Hanno Becker
9db697e8c6 Async operations: Simplify restart logic 2019-08-12 17:05:03 +01:00
Hanno Becker
4ec73cb251 Restructure SrvKeyExchange: Move parsing code 2019-08-12 17:05:03 +01:00
Hanno Becker
09d236419e Share code between In-CliKeyExch and Out-CliKeyExch
The postprocessing code for the server-side incoming client key
exchange and the client-side outgoing client key exchange both
contain the same code-paths for building the premaster secret
depending on the chosen ciphersuite (e.g., for ECDHE-PSK,
concatenating the ECDHE secret with the chosen PSK).

This commit moves this common code to ssl_tls.c, allowing
client- and server-side to share it.
2019-08-12 17:05:03 +01:00
Hanno Becker
d116e82268 Restructure incoming CliKeyExch: Shorten postprocessing
This commit subsumes multiple branches of
ssl_client_key_exchange_postprocess() that call
mbedtls_ssl_psk_derive_premaster().
2019-08-12 17:05:03 +01:00
Hanno Becker
2eb716d626 Restructure incoming CliKeyExch: Remove old code
The code from the previous function ssl_parse_client_key_exchange()
has been entirely moved to one of the newly introduced subroutines
and is no longer needed. This commit removes it.
2019-08-12 17:05:03 +01:00
Hanno Becker
e7c4eed9b8 Restructure incoming CliKeyExch: Parsing code 2019-08-12 17:05:03 +01:00
Hanno Becker
1e23af8fa8 Restructure incoming CliKeyExch: Move PMS assembly code
After parsing and performing key generation operations,
the server-side incoming ClientKeyExchange handling includes
code-paths to assembly the PreMasterSecret (PMS) from the
available keying material, the exact assembly procedure
depending on which ciphersuite is in use. E.g., in an
(EC)DHE-PSK ciphersuite, the (EC)DHE secret would be concatenated
with the PSK to form the PMS.

This assembly of the PMS logically comes done after the ClientKeyExchange
has been parsed and the respective keying material has been generated,
and this commit moves it to the new postprocessing function
ssl_client_key_exchange_postprocess().
2019-08-12 17:05:03 +01:00
Hanno Becker
dc8bfb9001 Restructure incoming CliKeyExch: Move key derivation code
This commit moves the generation of the master secret and session keys
from the premaster secret (done in mbedtlsssl_derive_keys()) from the
previous ClientKeyExchange parsing function ssl_parse_client_key_exchange()
to the new postprocessing function ssl_client_key_exchange_postprocess().
2019-08-12 17:05:03 +01:00
Hanno Becker
7ec345d95f Restructure incoming CliKeyExch: Add frame for restructuring
This commit adds declarations and dummy implementations for
the restructured incoming client key exchange handling that
will replace the previous ssl_parse_client_key_exchange().

The entry point for the CliKeyExchange handling that is called
from the handshake state machine is

   `ssl_process_client_key_exchange()`,

splitting the processing into the following steps:

- Fetching: Read next message from the messaging layer
            and check that it has the correct type.
            The ClientKeyExchange message is never
            omitted, so there is no ambiguity in what
            to expect, and hence no dedicated preparation
            step as for other handshake states.
- Parsing:  Parse the ClientKeyExchange message and
            use the information in it to derive keying
            material such as the shared (EC)DHE secret.
- Postprocessing:
            Compute the session keys from the available
            keying material. This splits in two steps:
            (1) Build the PreMasterSecret (PMS) from the
                available keying material, e.g. concatenate
                the (EC)DHE secret with a PSK, if used.
            (2) Extract the MasterSecret and Session Keys
                from the PreMasterSecret.

The subsequent commits will scatter the code from the previous
monolithic function ssl_parse_client_key_exchange() among those
dedicated functions, commenting out each part of
ssl_parse_client_key_exchange() that has already been dealt with.
This gradual progression is meant to ease reviewing. Once all
code has been moved and all changes explained,
ssl_parse_client_key_exchange() will be removed.
2019-08-12 17:05:03 +01:00
Hanno Becker
8844055b0e Remove compression field from SSL session if compression disabled 2019-08-01 10:11:20 +02:00
Hanno Becker
93de2965d0 Fix rebase slip 2019-07-30 16:56:25 +02:00
Hanno Becker
de62da9d3c Use separate functions to pend fatal and non-fatal alerts 2019-07-24 13:45:35 +01:00
Hanno Becker
1facd552fc Replace xxx_send_alert by xxx_pend_alert to save code 2019-07-24 13:20:27 +01:00
Simon Butcher
3b014fc23a Merge remote-tracking branch 'origin/pr/604' into baremetal 2019-07-23 16:16:24 +01:00
Hanno Becker
981f81dc30 Add missing uses of mbedtls_ssl_get_minor() 2019-07-19 16:12:54 +01:00
Hanno Becker
f1bc9e1c69 Introduce helper functions to traverse signature hashes 2019-07-17 10:19:27 +01:00
Hanno Becker
0af717b520 Don't use mbedtls_ssL_set_calc_verify_md writing CertificateRequest
mbedtls_ssl_set_calc_verify_md() serves two purposes:
(a) It checks whether a hash algorithm is suitable to be used
    in the CertificateVerify message.
(b) It updates the function callback pointing to the function that
    computes handshake transcript for the CertificateVerify message
    w.r.t. the chosen hash function.

Step (b) is only necessary when receiving the CertificateVerify
message, while writing the CertificateRequest only involves (a).

This commit modifies the writing code for the CertificateRequest
message to inline the check (a) and thereby avoiding the call to
mbedtls_ssl_calc_verify_md().
2019-07-17 10:19:27 +01:00
Simon Butcher
feb1cee36e Merge remote-tracking branch 'origin/pr/602' into baremetal 2019-07-15 19:24:11 +01:00
Hanno Becker
a4a9c696c1 Introduce helper macro for traversal of supported EC TLS IDs 2019-07-12 15:25:03 +01:00
Hanno Becker
84fb902ea5 Work on client-provided supported EC TLS ID list in-place 2019-07-12 15:25:01 +01:00
Hanno Becker
004619fa25 Store TLS curve ID instead of information structure
This will reduce the number of grp ID <-> tls ID <-> curve info structs
conversions once a single EC can be hardcoded through its TLS ID.
2019-07-12 15:19:43 +01:00
Hanno Becker
18729aeaac Guard RSA-only max_major/minor_ver fields from SSL handshake params
The fields
- mbedtls_ssl_handshake_params::max_major_ver,
- mbedtls_ssl_handshake_params::max_minor_ver
are used only for server-side RSA-based key exchanges
can be removed otherwise.
2019-07-12 15:15:07 +01:00
Hanno Becker
381eaa5976 Remove min/maj version from SSL context if only one version enabled
If the minor/major version is enforced at compile-time, the `major_ver`
and `minor_ver` fields in `mbedtls_ssl_context` are redundant and can
be removed.
2019-07-12 15:15:07 +01:00
Hanno Becker
2881d80138 Introduce getter function for max/min SSL version
This is a first step towards hardcoding ssl->{major|minor}_ver
in configurations which accept only a single version.
2019-07-12 15:15:06 +01:00
Hanno Becker
3fa1ee567c Set SSL minor version only after validation 2019-07-12 15:14:53 +01:00
Hanno Becker
e965bd397e Allow hardcoding of min/max minor/major SSL version at compile-time
This commit introduces the numeric compile-time constants

- MBEDTLS_SSL_CONF_MIN_MINOR_VER
- MBEDTLS_SSL_CONF_MAX_MINOR_VER
- MBEDTLS_SSL_CONF_MIN_MAJOR_VER
- MBEDTLS_SSL_CONF_MAX_MAJOR_VER

which, when defined, overwrite the runtime configurable fields
mbedtls_ssl_config::min_major_ver etc. in the SSL configuration.

As for the preceding case of the ExtendedMasterSecret configuration,
it also introduces and puts to use getter functions for these variables
which evaluate to either a field access or the macro value, maintaining
readability of the code.

The runtime configuration API mbedtls_ssl_conf_{min|max}_version()
is kept for now but has no effect if MBEDTLS_SSL_CONF_XXX are set.
This is likely to be changed in a later commit but deliberately omitted
for now, in order to be able to study code-size benefits earlier in the
process.
2019-07-12 15:14:51 +01:00
Hanno Becker
f4d6b49352 Allow use of continue in single-ciphersuite 'loops' 2019-07-08 11:23:24 +01:00
Hanno Becker
73f4cb126d Rename XXX_SINGLE_CIPHERSUITE -> XXX_CONF_SINGLE_CIPHERSUITE
This is in line with the other configurations options used
to hardcoded aspects of the SSL configuration.
2019-07-08 11:23:24 +01:00
Hanno Becker
e02758c9c8 Remove ciphersuite from SSL session if single suite hardcoded
If MBEDTLS_SSL_SINGLE_CIPHERSUITE is enabled, the type

  mbedtls_ssl_ciphersuite_handle_t

is logically a boolean (concretely realized as `unsigned char`),
containing the invalid handle and the unique valid handle, which
represents the single enabled ciphersuite.

The SSL session structure mbedtls_ssl_session contains an instance
of mbedtls_ssl_ciphersuite_handle_t which is guaranteed to be valid,
and which is hence redundant in any two-valued implementation of
mbedtls_ssl_ciphersuite_handle_t.

This commit replaces read-uses of

  mbedtls_ssl_session::ciphersuite_info

by a getter functions which, and defines this getter function
either by just reading the field from the session structure
(in case MBEDTLS_SSL_SINGLE_CIPHERSUITE is disabled), or by
returning the single valid ciphersuite handle (in case
MBEDTLS_SSL_SINGLE_CIPHERSUITE is enabled) and removing the
field from mbedtls_ssl_session in this case.
2019-07-08 11:23:24 +01:00
Hanno Becker
df64596733 Remove ciphersuite from handshake params if single suite hardcoded
If MBEDTLS_SSL_SINGLE_CIPHERSUITE is enabled, the type

  mbedtls_ssl_ciphersuite_handle_t

is logically a boolean (concretely realized as `unsigned char`),
containing the invalid handle and the unique valid handle, which
represents the single enabled ciphersuite.

The SSL handshake structure mbedtls_ssl_handshake_params contains
an instance of mbedtls_ssl_ciphersuite_handle_t which is guaranteed
to be valid, and which is hence redundant in any two-valued
implementation of mbedtls_ssl_ciphersuite_handle_t.

This commit replaces read-uses of

  mbedtls_ssl_handshake_params::ciphersuite_info

by a getter functions which, and defines this getter function
either by just reading the field from the handshake structure
(in case MBEDTLS_SSL_SINGLE_CIPHERSUITE is disabled), or by
returning the single valid ciphersuite handle (in case
MBEDTLS_SSL_SINGLE_CIPHERSUITE is enabled) and removing the
field from mbedtls_ssl_handshake_params in this case.
2019-07-08 11:23:24 +01:00
Hanno Becker
2d46b4f2a1 Adapt ClientHello parsing to case of single hardcoded ciphersuite
This commit adapts the ClientHello parsing routines in ssl_srv.c
to use the ciphersuite traversal macros

  MBEDTLS_SSL_BEGIN_FOR_EACH_CIPHERSUITE
  MBEDTLS_SSL_END_FOR_EACH_CIPHERSUITE

introduced in the last commit, thereby making them work
both with and without MBEDTLS_SSL_SINGLE_CIPHERSUITE.

Another notable change concerns the ssl_ciphersuite_match:
Previous, this function would take a ciphersuite ID and a
pointer to a destination ciphersuite info structure as input
and write eithe NULL or a valid ciphersuite info structure
to that destination address, depending on whether the suite
corresponding to the given ID was suitable or not. The
function would always return 0 outside of a fatal error.
This commit changes this to ssl_ciphersuite_is_match() which
instead already takes a ciphersuite handle (which outside
of a hardcoded ciphersuite is the same as the ptr to a
ciphersuite info structure) and returns 0 or 1 (or a
negative error code in case of a fatal error) indicating
whether the suite corresponding to the handle was acceptable
or not. The conversion of the ciphersuite ID to the ciphersuite
info structure is done prior to calling ssl_ciphersuite_is_match().
2019-07-08 11:23:17 +01:00
Hanno Becker
473f98f2e0 Introduce ciphersuite handle type
This commit introduces an internal zero-cost abstraction layer for
SSL ciphersuites: Instead of addressing ciphersuites via pointers
to instances of mbedtls_ssl_ciphersuite_t and accessing their fields
directly, this commit introduces an opaque type

  mbedtls_ssl_ciphersuite_handle_t,

and getter functions

  mbedtls_ssl_suite_get_xxx()

operating on ciphersuite handles.

The role of NULL is played by a new macro constant

  MBEDTLS_SSL_CIPHERSUITE_INVALID_HANDLE

which results of functions returning handles can be checked against.
(For example, when doing a lookup of a ciphersuite from a peer-provided
ciphersuite ID in the per's Hello message).

The getter functions have the validity of the handle as a precondition
and are undefined if the handle is invalid.

So far, there's only one implementation of this abstraction layer, namely

  mbedtls_ssl_ciphersuite_handle_t being mbedtls_ssl_ciphersuite_t const *

and

  getter functions being field accesses.

In subsequent commits, however, the abstraction layer will be useful
to save code in the situation where only a single ciphersuite is enabled.
2019-07-08 11:17:53 +01:00
Manuel Pégourié-Gonnard
5455afd74e
Merge pull request #599 from ARMmbed/baremetal-ec-preparation
[Baremetal] Avoid heap-allocation for client-supported elliptic curves
2019-07-05 14:16:41 +02:00
Hanno Becker
d3b2fcb7c6 Don't store client-supported ECs in heap-allocated buffer
So far, the client-proposed list of elliptic curves was stored for the
duration of the entire handshake in a heap-allocated buffer referenced
from mbedtls_ssl_handshake_params::curves. It is used in the following
places:
1) When the server chooses a suitable ciphersuite, it checks that
   it has a certificate matching the ciphersuite; in particular, if
   the ciphersuite involves ECDHE, the server needs an EC certificate
   with a curve suitable for the client.
2) When performing the ECDHE key exchange, the server choose one
   curve among those proposed by the client which matches the server's
   own supported curve configuration.

This commit removes the hold back the entire client-side curve list
during the handshake, by performing (1) and (2) on during ClientHello
parsing, and in case of (2) only remembering the curve chosen for ECDHE
within mbedtls_ssl_handshake_params.
2019-07-04 12:41:08 +01:00
Hanno Becker
ece325c8dd Allow compile-time configuration of PRNG in SSL module
Introduces MBEDTLS_SSL_CONF_RNG to allow configuring the
RNG to be used by the SSL module at compile-time.

Impact on code-size:

|  | GCC 8.2.1 | ARMC5 5.06 | ARMC6 6.12 |
| --- | --- | --- | --- |
| `libmbedtls.a` before | 23535 | 24089 | 27103 |
| `libmbedtls.a` after | 23471 | 24077 | 27045 |
| gain in Bytes | 64 | 12 | 58 |
2019-07-04 10:27:41 +01:00
Manuel Pégourié-Gonnard
de8869c529 Merge remote-tracking branch 'restricted/pr/608' into baremetal-proposed
* restricted/pr/608:
  programs: Make `make clean` clean all programs always
  ssl_tls: Enable Suite B with subset of ECP curves
  windows: Fix Release x64 configuration
  timing: Remove redundant include file
  net_sockets: Fix typo in net_would_block()
  Add all.sh component that exercises invalid_param checks
  Remove mbedtls_param_failed from programs
  Make it easier to define MBEDTLS_PARAM_FAILED as assert
  Make test suites compatible with #include <assert.h>
  Pass -m32 to the linker as well
  Update library to 2.16.2
  Use 'config.pl baremetal' in all.sh
  Clarify ChangeLog entry for fix to #1628
  Fix #2370, minor typos and spelling mistakes
  Add Changelog entry for clang test-ref-configs.pl fix
  Enable more compiler warnings in tests/Makefile
  Change file scoping of test helpers.function
2019-07-03 10:31:46 +02:00
Manuel Pégourié-Gonnard
44ba6b0d26 Merge remote-tracking branch 'restricted/pr/594' into baremetal-proposed
* restricted/pr/594:
  Adapt baremetal.h and baremetal.sh
  Don't incl. CAs in CertReq message in baremetal build
  Allow config'n of incl of CertificateReq CA list Y/N at compile-time
  Allow configuration of endpoint (cli/srv) at compile-time
  Allow configuration of read timeouts at compile-time
  Allow configuration of ConnectionID at compile-time
  Allow compile-time configuration of legacy renegotiation
  Allow compile-time configuration of authentication mode
  Allow compile-time configuration of DTLS badmac limit
  Allow compile-time configuration of DTLS anti replay
2019-07-03 10:22:28 +02:00
Manuel Pégourié-Gonnard
37261e6f6b Merge remote-tracking branch 'restricted/pr/601' into baremetal-proposed
* restricted/pr/601: (27 commits)
  Fix compile-time guard for optional field in struct
  Move code to reduce probability of conflicts
  Fix typos caught by check-names.sh
  Clarify conditions related to resumption in client
  Introduce getter function for renego_status
  Add getter function for handshake->resume
  Remove now-redundant code
  Remove cache callbacks from config on client
  Fix a few style issues
  Expand documentation of new options a bit
  Fix renaming oversight in documentation
  Remove backticks in doxygen in config.h
  Declare dependency on tickets for two ssl-opt.sh tests
  Exclude new negative options from config.pl full
  Restore config.h defaults
  Address review comments
  Fix ssl_cli resumption guards
  Fix check-files, check-names and check-generated-features
  Add test to all.sh
  Add changelog entry
  ...
2019-07-03 10:04:13 +02:00
Manuel Pégourié-Gonnard
417d2ce076 Merge remote-tracking branch 'restricted/pr/584' into baremetal-proposed
* restricted/pr/584: (140 commits)
  Remove superfluous new line in x509.c
  Add comment about X.509 name comparison of buffer with itself
  [Fixup] Add missing PK release call in Cert Verify parsing
  Fix guard controlling whether nested acquire calls are allowed
  Add X.509 CRT test for nested calls for CRT frame / PK acquire
  Don't return threading error on release()-without-acquire() calls
  Don't allow nested CRT acquire()-calls if MBEDTLS_X509_ALWAYS_FLUSH
  Make X.509 CRT cache reference counting unconditional
  Remove memory buffer alloc from i386 test in all.sh
  Don't mention pk_sign() in the context of public-key contexts
  Don't use assertion for failures of mbedtls_x509_crt_x_acquire()
  Fix copy pasta in x509_crt.h
  Reference copy-less versions of X.509 CRT frame/PK getters
  x509_crt.c: Add blank line to increase readability
  [FIXUP] Fix bug in ASN.1 traversal of silently ignored tag
  [FIXUP] Fix typo in declaration of mbedtls_x509_memcasecmp()
  Move signature-info extraction out of MBEDTLS_X509_REMOVE_INFO
  Fix certificate validity checking logic to work with !TIME_DATE
  Simplify X.509 CRT version check in UID parsing
  Remove unused variable warning in on-demand X.509 parsing
  ...
2019-07-03 10:03:45 +02:00
Hanno Becker
c2cfdaa693 Allow config'n of incl of CertificateReq CA list Y/N at compile-time
Introduces MBEDTLS_SSL_CONF_CERT_REQ_CA_LIST which allows to configure
at compile-time whether a CA list should be included in the
CertificateRequest message sent by the server.

Impact on code-size:

|  | GCC 8.2.1 | ARMC5 5.06 | ARMC6 6.12 |
| --- | --- | --- | --- |
| `libmbedtls.a` before  | 23131 | 23805 | 26673 |
| `libmbedtls.a` after | 23099 | 23781 | 26639 |
| gain in Bytes | 32 | 24 | 34 |
2019-07-02 16:42:45 +01:00
Hanno Becker
2d9623f7d5 Allow configuration of endpoint (cli/srv) at compile-time
Introduces MBEDTLS_SSL_CONF_ENDPOINT to allow to choose between
server- or client-builds at compile-time.

Impact on code-size:

|  | GCC 8.2.1 | ARMC5 5.06 | ARMC6 6.12 |
| --- | --- | --- | --- |
| `libmbedtls.a` (client only) before  | 18355 | 18815 | 21485 |
| `libmbedtls.a` (client only) after | 18219 | 18683 | 21347 |
| gain in Bytes (client only) | 136 | 132 | 138 |
| `libmbedtls.a` (server only) before  | 18715 | 18987 | 21883 |
| `libmbedtls.a` (server only) after | 18595 | 18823 | 21717 |
| gain in Bytes (server only) | 120 | 164 | 166 |
2019-07-02 16:42:41 +01:00
Hanno Becker
b0b2b67568 Allow compile-time configuration of legacy renegotiation
Introduces MBEDTLS_SSL_CONF_ALLOW_LEGACY_RENEGOTIATION
allowing to configure enforcing secure renegotiation at
compile-time.

Impact on code-size:

|  | GCC | ARMC5 | ARMC6 |
| --- | --- | --- | --- |
| `libmbedtls.a` after  | 23379 | 23929 | 27727 |
| `libmbedtls.a` before | 23307 | 23865 | 27615 |
| gain in Bytes | 72 | 64 | 112 |
2019-07-02 16:41:34 +01:00
Hanno Becker
acd4fc0ac9 Allow compile-time configuration of authentication mode
Introduces MBEDTLS_SSL_CONF_AUTHMODE to fix the authentication
mode (none, optional, mandatory) at compile-time.

Impact on code-size:

|  | GCC | ARMC5 | ARMC6 |
| --- | --- | --- | --- |
| `libmbedtls.a` before | 23487 | 24025 | 27885 |
| `libmbedtls.a` after  | 23379 | 23929 | 27727 |
| gain in Bytes | 108 | 96 | 157 |
2019-07-02 16:41:29 +01:00
Hanno Becker
bc6b59859f [Fixup] Add missing PK release call in Cert Verify parsing
mbedtls_ssl_read() can fail non-fatally, in which case
ssl_parse_certificate_verify() returned immediately without
calling mbedtls_x509_crt_pk_release(), which in turn lead
to a fatal error because of nested acquire calls in the
next call to the function.
2019-07-02 15:36:44 +01:00
Manuel Pégourié-Gonnard
754b9f32db Introduce getter function for renego_status
While not strictly related to this PR, this change improves readability in
some resumption-related runtime conditions that previously had rather ugly
preprocessor directives in the middle of already complex predicates.
2019-07-02 15:13:18 +02:00
Manuel Pégourié-Gonnard
3652e99100 Add getter function for handshake->resume
This makes the code more readable by having fewer #ifdefs all over the place.
2019-07-02 15:13:18 +02:00
Jarno Lamsa
29f2dd0a7b Address review comments 2019-07-02 15:12:29 +02:00
Jarno Lamsa
59bd12bf14 Add new config MBEDTLS_SSL_SESSION_RESUMPTION
Add a new configuration option MBEDTLS_SSL_SESSION_RESUMPTION
to enable/disable the session resumption feature including
ticket and cache based session resumption.
2019-07-02 15:12:29 +02:00
Jarno Lamsa
7be14065e2 Add config MBEDTLS_SSL_SESSION_CACHE
Add configuration option MBEDTLS_SSL_SESSION_CACHE to control
enabling/disabling of the cache based session resumption.
2019-07-02 15:12:29 +02:00
Hanno Becker
abd929c89c Merge branch 'mbedtls-2.16' into baremetal-2.16-01_07_19 2019-07-01 11:25:42 +01:00
Hanno Becker
2224ccf390 Don't use assertion for failures of mbedtls_x509_crt_x_acquire()
These functions may afil in a regular run, e.g. due to an out of memory
error.
2019-06-28 14:48:31 +01:00
Hanno Becker
5f268b3cf6 Don't allow change of CRT frame returned by x509_crt_frame_acquire() 2019-06-25 09:10:57 +01:00
Hanno Becker
c6d1c3ed1c Remove frame/pk parameter from mbedtls_x509_crt_xxx_release() 2019-06-25 09:07:16 +01:00
Hanno Becker
1e11f217d4 Solely use raw X.509 name data references including SEQUENCE header
So far, the CRT frame structure `mbedtls_x509_crt_frame` used
as `issuer_raw` and `subject_raw` the _content_ of the ASN.1
name structure for issuer resp. subject. This was in contrast
to the fields `issuer_raw` and `subject_raw` from the legacy
`mbedtls_x509_crt` structure, and caused some information
duplication by having both variants `xxx_no_hdr` and `xxx_with_hdr`
in `mbedtls_x509_crt` and `mbedtls_x509_crt_frame`.

This commit removes this mismatch by solely using the legacy
form of `issuer_raw` and `subject_raw`, i.e. those _including_
the ASN.1 name header.
2019-06-25 09:07:16 +01:00
Hanno Becker
828a8c08b6 Add compile-guard for < TLS1.2 path in server-side ssl_pick_cert()
Minor code-size optimization along the way.
2019-06-25 09:06:26 +01:00
Hanno Becker
73cd8d8adc Make use of acquire/release in ssl_parse_certificate_verify() 2019-06-25 09:06:26 +01:00
Hanno Becker
232f8faf00 Make use of CRT acquire/release in ssl_write_certificate_request() 2019-06-25 09:06:26 +01:00
Hanno Becker
30649f7a17 Make use of CRT acquire/release in server-side ssl_pick_cert() 2019-06-25 09:06:26 +01:00
Hanno Becker
371e0e4573 Determine whether CRT is initialized or not through raw data pointer
Previously, `mbedtls_x509_crt_der_internal()` used the `version` field
(which is `0` after initialization but strictly greater than 0 once a
CRT has successfully been parsed) to determine whether an
`mbedtls_x509_crt` instance had already been setup.

Preparating for the removal of `version` from the structure, this
commit modifies the code to instead peek at the raw data pointer,
which is NULL as long as the CRT structure hasn't been setup with a CRT,
and will be kept in the new CRT structure.
2019-06-25 09:06:26 +01:00
Hanno Becker
74b89f6051 Use private key to check suitability of PK type when picking srv CRT
The server-side routine `ssl_pick_cert()` is responsible for
picking a suitable CRT from the list of CRTs configured on the
server. For that, it previously used the public key context
from the certificate to check whether its type (including the
curve type for ECC keys) suits the ciphersuite and the client's
preferences.

This commit changes the code to instead use the PK context
holding the corresponding private key. For inferring the type
of the key, this makes no difference, and it removes a PK-from-CRT
extraction step which, if CRTs are stored raw, is costly in terms
of computation and memory: CRTs need to be parsed, and memory needs
to be allocated for the PK context.
2019-06-25 09:00:25 +01:00
Hanno Becker
81bb4d0378 Simplify server-side ssl_decrypt_encrypted_pms()
The server-side routine `ssl_decrypt_encrypted_pms()` is
responsible for decrypting the RSA-encrypted PMS in case of
an RSA-based ciphersuite.

Previously, the code checked that the length of the PMS sent
by the client matches the bit length of the RSA key. This commit
removes this check -- thereby removing the need to access the
server's own CRT -- because the RSA decryption routine performs
this check itself, too.
2019-06-25 09:00:25 +01:00
Hanno Becker
1ab322bb51 Remove extended_ms field from HS param if ExtendedMS enforced 2019-06-25 08:42:20 +01:00
Hanno Becker
a49ec56f51 Introduce getter function for extended_ms field in HS struct 2019-06-25 08:42:20 +01:00
Hanno Becker
03b64fa6c1 Rearrange ExtendedMasterSecret parsing logic
`mbedtls_ssl_handshake_params::extended_ms` holds the state of the
ExtendedMasterSecret extension in the current handshake. Initially
set to 'disabled' for both client and server,
- the client sets it to 'enabled' as soon as it finds the ExtendedMS
  extension in the `ServerHello` and it has advertised that extension
  in its ClientHello,
- the server sets it to 'enabled' as soon as it finds the ExtendedMS
  extension in the `ClientHello` and is willing to advertise is in its
  `ServerHello`.

This commit slightly restructures this logic in prepraration for the
removal of `mbedtls_ssl_handshake_params::extended_ms` in case both
the use and the enforcement of the ExtendedMasterSecret extension have
been fixed at compile-time. Namely, in this case there is no need for
the `extended_ms` field in the handshake structure, as the ExtendedMS
must be in use if the handshake progresses beyond the Hello stage.

Paving the way for the removal of mbedtls_ssl_handshake_params::extended_ms
this commit introduces a temporary variable tracking the presence of the
ExtendedMS extension in the ClientHello/ServerHello messages, leaving
the derivation of `extended_ms` (and potential failure) to the end of
the parsing routine.
2019-06-25 08:42:20 +01:00
Hanno Becker
aabbb582eb Exemplify harcoding SSL config at compile-time in example of ExtMS
This commit is the first in a series demonstrating how code-size
can be reduced by hardcoding parts of the SSL configuration at
compile-time, focusing on the example of the configuration of
the ExtendedMasterSecret extension.

The flexibility of an SSL configuration defined a runtime vs.
compile-time is necessary for the use of Mbed TLS as a
dynamically linked library, but is undesirable in constrained
environments because it introduces the following overhead:
- Definition of SSL configuration API (code-size overhead)
  (and on the application-side: The API needs to be called)
- Additional fields in the SSL configuration (RAM overhead,
  and potentially code-size overhead if structures grow
  beyond immediate-offset bounds).
- Dereferencing is needed to obtain configuration settings.
- Code contains branches and potentially additional structure
  fields to distinguish between different configurations.

Considering the example of the ExtendedMasterSecret extension,
this instantiates as follows:
- mbedtls_ssl_conf_extended_master_secret() and
  mbedtls_ssl_conf_extended_master_secret_enforced()
  are introduced to configure the ExtendedMasterSecret extension.
- mbedtls_ssl_config contains bitflags `extended_ms` and
  `enforce_extended_master_secret` reflecting the runtime
  configuration of the ExtendedMasterSecret extension.
- Whenever we need to access these fields, we need a chain
  of dereferences `ssl->conf->extended_ms`.
- Determining whether Client/Server should write the
  ExtendedMasterSecret extension needs a branch
  depending on `extended_ms`, and the state of the
  ExtendedMasterSecret negotiation needs to be stored in a new
  handshake-local variable mbedtls_ssl_handshake_params::extended_ms.
  Finally (that's the point of ExtendedMasterSecret) key derivation
  depends on this handshake-local state of ExtendedMasterSecret.

All this is unnecessary if it is known at compile-time that the
ExtendedMasterSecret extension is used and enforced:
- No API calls are necessary because the configuration is fixed
  at compile-time.
- No SSL config fields are necessary because there are corresponding
  compile-time constants instead.
- Accordingly, no dereferences for field accesses are necessary,
  and these accesses can instead be replaced by the corresponding
  compile-time constants.
- Branches can be eliminated at compile-time because the compiler
  knows the configuration. Also, specifically for the ExtendedMasterSecret
  extension, the field `extended_ms` in the handshake structure
  is unnecessary, because we can fail immediately during the Hello-
  stage of the handshake if the ExtendedMasterSecret extension
  is not negotiated; accordingly, the non-ExtendedMS code-path
  can be eliminated from the key derivation logic.

A way needs to be found to allow fixing parts of the SSL configuration
at compile-time which removes this overhead in case it is used,
while at the same time maintaining readability and backwards
compatibility.

This commit proposes the following approach:

From the user perspective, for aspect of the SSL configuration
mbedtls_ssl_config that should be configurable at compile-time,
introduce a compile-time option MBEDTLS_SSL_CONF_FIELD_NAME.
If this option is not defined, the field is kept and configurable
at runtime as usual. If the option is defined, the field is logically
forced to the value of the option at compile time.

Internally, read-access to fields in the SSL configuration which are
configurable at compile-time gets replaced by new `static inline` getter
functions which evaluate to the corresponding field access or to the
constant MBEDTLS_SSL_CONF_FIELD_NAME, depending on whether the latter
is defined or not.

Write-access to fields which are configurable at compile-time needs
to be removed: Specifically, the corresponding API itself either
needs to be removed or replaced by a stub function without effect.
This commit takes the latter approach, which has the benefit of
not requiring any change on the example applications, but introducing
the risk of mismatching API calls and compile-time configuration,
in case a user doesn't correctly keep track of which parts of the
configuration have been fixed at compile-time, and which haven't.
Write-access for the purpose of setting defaults is simply omitted.
2019-06-25 08:42:20 +01:00
Hanno Becker
5882dd0856 Remove CRT digest from SSL session if !RENEGO + !KEEP_PEER_CERT
If `MBEDTLS_SSL_KEEP_PEER_CERTIFICATE` is not set, `mbedtls_ssl_session`
contains the digest of the peer's certificate for the sole purpose of
detecting a CRT change on renegotiation. Hence, it is not needed if
renegotiation is disabled.

This commit removes the `peer_cert_digest` fields (and friends) from
`mbedtls_ssl_session` if
   `!MBEDTLS_SSL_KEEP_PEER_CERTIFICATE + !MBEDTLS_SSL_RENEGOTIATION`,
which is a sensible configuration for constrained devices.

Apart from straightforward replacements of
   `if !defined(MBEDTLS_SSL_KEEP_PEER_CERTIFICATE)`
by
   `if !defined(MBEDTLS_SSL_KEEP_PEER_CERTIFICATE) && \
        defined(MBEDTLS_SSL_RENEGOTIATION)`,
there's one notable change: On the server-side, the CertificateVerify
parsing function is a no-op if the client hasn't sent a certificate.
So far, this was determined by either looking at the peer CRT or the
peer CRT digest in the SSL session structure (depending on the setting
of `MBEDTLS_SSL_KEEP_PEER_CERTIFICATE`), which now no longer works if
`MBEDTLS_SSL_KEEP_PEER_CERTIFICATE` is unset. Instead, this function
now checks whether the temporary copy of the peer's public key within
the handshake structure is initialized or not (which is also a
beneficial simplification in its own right, because the pubkey is
all the function needs anyway).
2019-06-19 16:56:51 +01:00
Hanno Becker
cd90126ab3 Adapt client auth detection in ssl_parse_certificate_verify()
The server expects a CertificateVerify message only if it has
previously received a Certificate from the client.

So far, this was detected by looking at the `peer_cert` field
in the current session. Preparing to remove the latter, this
commit changes this to instead determine the presence of a peer
certificate by checking the new `peer_cert_digest` pointer.
2019-06-19 10:25:02 +01:00
Hanno Becker
0833c1082b Adapt server-side signature verification to use raw public key
We must dispatch between the peer's public key stored as part of
the peer's CRT in the current session structure (situation until
now, and future behaviour if MBEDTLS_SSL_KEEP_PEER_CERTIFICATE is
enabled), and the sole public key stored in the handshake structure
(new, if MBEDTLS_SSL_KEEP_PEER_CERTIFICATE is disabled).
2019-06-19 10:25:02 +01:00
Hanno Becker
ae39b9eb48 Make use of macro and helper detecting whether CertRequest allowed
This commit simplifies the client-side code for outgoing CertificateVerify
messages, and server-side code for outgoing CertificateRequest messages and
incoming CertificateVerify messages, through the use of the macro

   `MBEDTLS_KEY_EXCHANGE__CERT_REQ_ALLOWED__ENABLED`

indicating whether a ciphersuite allowing CertificateRequest messages
is enabled in the configuration, as well as the helper function

   `mbedtls_ssl_ciphersuite_cert_req_allowed()`

indicating whether a particular ciphersuite allows CertificateRequest
messages.

These were already used in the client-side code to simplify the
parsing functions for CertificateRequest messages.
2019-06-19 10:25:01 +01:00
Simon Butcher
c725e4b34e Merge remote-tracking branch 'origin/pr/590' into baremetal 2019-06-17 17:57:26 +01:00
Manuel Pégourié-Gonnard
ec1c222947 Fix a few style issues 2019-06-12 10:18:26 +02:00
Jarno Lamsa
20095afc58 Changes according to review comments 2019-06-11 17:16:58 +03:00
Jarno Lamsa
842be16800 Check for the enforcing and fail handshake if the peer doesn't support 2019-06-10 15:05:33 +03:00
Manuel Pégourié-Gonnard
64c1681fbc Use new macros for all TLS/DTLS tests
sed -i -e 's/\([^ ]*transport\) == MBEDTLS_SSL_TRANSPORT_DATAGRAM/MBEDTLS_SSL_TRANSPORT_IS_DTLS( \1 )/' -e 's/\([^ ]*transport\) \(!= MBEDTLS_SSL_TRANSPORT_DATAGRAM\|== MBEDTLS_SSL_TRANSPORT_STREAM\)/MBEDTLS_SSL_TRANSPORT_IS_TLS( \1 )/' library/ssl_*.c

New sizes (see 2nd-previous commit for measuring script):

```

both
   text    data     bss     dec     hex filename
   1820       0       4    1824     720 debug.o (ex library/libmbedtls.a)
      0       0       0       0       0 net_sockets.o (ex library/libmbedtls.a)
    548       0       0     548     224 ssl_cache.o (ex library/libmbedtls.a)
  11155       0     596   11751    2de7 ssl_ciphersuites.o (ex library/libmbedtls.a)
  17156       0       0   17156    4304 ssl_cli.o (ex library/libmbedtls.a)
    460       0       0     460     1cc ssl_cookie.o (ex library/libmbedtls.a)
  17649       0       0   17649    44f1 ssl_srv.o (ex library/libmbedtls.a)
    800       0       0     800     320 ssl_ticket.o (ex library/libmbedtls.a)
  39286      60       0   39346    99b2 ssl_tls.o (ex library/libmbedtls.a)
  88874      60     600   89534   15dbe (TOTALS)

DTLS-only
   text    data     bss     dec     hex filename
   1820       0       4    1824     720 debug.o (ex library/libmbedtls.a)
      0       0       0       0       0 net_sockets.o (ex library/libmbedtls.a)
    548       0       0     548     224 ssl_cache.o (ex library/libmbedtls.a)
  11155       0     596   11751    2de7 ssl_ciphersuites.o (ex library/libmbedtls.a)
  16948       0       0   16948    4234 ssl_cli.o (ex library/libmbedtls.a)
    460       0       0     460     1cc ssl_cookie.o (ex library/libmbedtls.a)
  17437       0       0   17437    441d ssl_srv.o (ex library/libmbedtls.a)
    800       0       0     800     320 ssl_ticket.o (ex library/libmbedtls.a)
  38147      60       0   38207    953f ssl_tls.o (ex library/libmbedtls.a)
  87315      60     600   87975   157a7 (TOTALS)

TLS-only
   text    data     bss     dec     hex filename
   1820       0       4    1824     720 debug.o (ex library/libmbedtls.a)
      0       0       0       0       0 net_sockets.o (ex library/libmbedtls.a)
    548       0       0     548     224 ssl_cache.o (ex library/libmbedtls.a)
  11155       0     596   11751    2de7 ssl_ciphersuites.o (ex library/libmbedtls.a)
  14912       0       0   14912    3a40 ssl_cli.o (ex library/libmbedtls.a)
    460       0       0     460     1cc ssl_cookie.o (ex library/libmbedtls.a)
  15868       0       0   15868    3dfc ssl_srv.o (ex library/libmbedtls.a)
    800       0       0     800     320 ssl_ticket.o (ex library/libmbedtls.a)
  27619      60       0   27679    6c1f ssl_tls.o (ex library/libmbedtls.a)
  73182      60     600   73842   12072 (TOTALS)
```
2019-06-06 13:19:59 +02:00
Manuel Pégourié-Gonnard
ff4bd9f405 Use new tools for all cases with TLS-specific code
This commit handles occurrences of case 2 and 3 in the following list:

1. Some DTLS-specific code with no TLS-specific code (most frequent)
2. Some specific code for each protocol
3. Some TLS-specific code with no DTLS-specific code (least frequent)

Case 3 previously had a weird structure in that the TLS-specific code was
always present, but the if structure was conditional on DTLS being enabled.
This is changed by this commit to a more logical structure where both the code
and the test are conditional on TLS being enabled.

Case 2 doesn't require any change in the code structure in general. However,
there is one occurrence where the if/else structure is simplified to assigning
the result of a boolean operation, and one occurrence where I also noticed a
useless use of `ssl_ep_len()` in a TLS-specific branch, that I turned to the
constant 0 as it makes more sense.

Case 1 will be handled in the next commit, as it can easily be handled in an
automated way - only cases 2 and 3 (sometimes) required manual intervention.

The list of occurrences for cases 2 and 3 was established manually by looking
for occurrences of '= MBEDTLS_SSL_TRANSPORT_' in the code and manually
checking if there was a TLS-specific branch.

New sizes (see previous commit for the measuring script):

```

both
   text    data     bss     dec     hex filename
   1820       0       4    1824     720 debug.o (ex library/libmbedtls.a)
      0       0       0       0       0 net_sockets.o (ex library/libmbedtls.a)
    548       0       0     548     224 ssl_cache.o (ex library/libmbedtls.a)
  11155       0     596   11751    2de7 ssl_ciphersuites.o (ex library/libmbedtls.a)
  17156       0       0   17156    4304 ssl_cli.o (ex library/libmbedtls.a)
    460       0       0     460     1cc ssl_cookie.o (ex library/libmbedtls.a)
  17649       0       0   17649    44f1 ssl_srv.o (ex library/libmbedtls.a)
    800       0       0     800     320 ssl_ticket.o (ex library/libmbedtls.a)
  39286      60       0   39346    99b2 ssl_tls.o (ex library/libmbedtls.a)
  88874      60     600   89534   15dbe (TOTALS)

DTLS-only
   text    data     bss     dec     hex filename
   1820       0       4    1824     720 debug.o (ex library/libmbedtls.a)
      0       0       0       0       0 net_sockets.o (ex library/libmbedtls.a)
    548       0       0     548     224 ssl_cache.o (ex library/libmbedtls.a)
  11155       0     596   11751    2de7 ssl_ciphersuites.o (ex library/libmbedtls.a)
  17068       0       0   17068    42ac ssl_cli.o (ex library/libmbedtls.a)
    460       0       0     460     1cc ssl_cookie.o (ex library/libmbedtls.a)
  17553       0       0   17553    4491 ssl_srv.o (ex library/libmbedtls.a)
    800       0       0     800     320 ssl_ticket.o (ex library/libmbedtls.a)
  38499      60       0   38559    969f ssl_tls.o (ex library/libmbedtls.a)
  87903      60     600   88563   159f3 (TOTALS)

TLS-only
   text    data     bss     dec     hex filename
   1820       0       4    1824     720 debug.o (ex library/libmbedtls.a)
      0       0       0       0       0 net_sockets.o (ex library/libmbedtls.a)
    548       0       0     548     224 ssl_cache.o (ex library/libmbedtls.a)
  11155       0     596   11751    2de7 ssl_ciphersuites.o (ex library/libmbedtls.a)
  14912       0       0   14912    3a40 ssl_cli.o (ex library/libmbedtls.a)
    460       0       0     460     1cc ssl_cookie.o (ex library/libmbedtls.a)
  15868       0       0   15868    3dfc ssl_srv.o (ex library/libmbedtls.a)
    800       0       0     800     320 ssl_ticket.o (ex library/libmbedtls.a)
  27619      60       0   27679    6c1f ssl_tls.o (ex library/libmbedtls.a)
  73182      60     600   73842   12072 (TOTALS)
```
2019-06-06 13:18:19 +02:00
Simon Butcher
0d1d76f987 Merge remote-tracking branch 'origin/pr/561' into baremetal 2019-05-29 15:09:24 +01:00
Simon Butcher
5a790f9214 Merge remote-tracking branch 'origin/pr/563' into baremetal 2019-05-24 15:06:16 +01:00
Hanno Becker
a5a2b08a05 Rename MBEDTLS_SSL_CID to MBEDTLS_SSL_DTLS_CONNECTION_ID
Files modified via

sed -i 's/MBEDTLS_SSL_CID\([^_]\|$\)/MBEDTLS_SSL_DTLS_CONNECTION_ID\1/g' **/*.c **/*.h **/*.sh **/*.function
2019-05-20 15:35:36 +01:00